Hayflick L
Department of Anatomy, University of California, San Francisco, School of Medicine, P.O. Box 89, The Sea Ranch, CA 95497, USA.
Br J Cancer. 2000 Oct;83(7):841-6. doi: 10.1054/bjoc.2000.1296.
Normal cultured cell populations are mortal but cells that are immortal are abnormal and most have properties of cancer cells. Nevertheless, this distinction becomes blurred because the terms 'mortality' and 'immortality' are subject to enormous variations in understanding. Forty years ago we showed that cell mortality and immortality are inextricably linked to longevity determination, ageing and cancer. We suggested that a counting mechanism existed in normal cells and that has now been identified as telomere attrition. This replicometer, in combination with the discovery of the enzyme telomerase, has gone very far in explaining why most normal somatic cells have a finite capacity to replicate both in vivo and in vitro and how immortal cancer cells circumvent this inevitability. It is suggested that telomere attrition may be better understood as a direct measure of longevity determination and to only have an indirect association with age changes.
正常培养的细胞群体是有寿命的，但永生的细胞是异常的，并且大多数具有癌细胞的特性。然而，这种区别变得模糊，因为“有寿命”和“永生”这两个术语在理解上存在巨大差异。四十年前我们表明，细胞的有寿命和永生与寿命的确定、衰老和癌症有着千丝万缕的联系。我们提出正常细胞中存在一种计数机制，现在已确定为端粒磨损。这种复制计量器，结合端粒酶的发现，在很大程度上解释了为什么大多数正常体细胞在体内和体外都具有有限的复制能力，以及永生癌细胞如何规避这种必然性。有人认为，端粒磨损可能更好地被理解为寿命确定的直接度量，而与年龄变化只有间接关联。
